Milk bottle cap



J. R. GAMMETER MILK BOTTLE CAP May 9, 1%39.

Filed April 2, 1935 J N K GAMMET E/ GM 1. 2

ATTORNEY Patented May 9, 1939 MILK BOTTLE CAP John It. Gammeter, Akron,Ohio, assignor of onehalf to Susan G. Gammeter, Akron, Ohio ApplicationApril 2, 1935, Serial No. 14,248

Claims. This invention relates to improvements in milk bottle caps andthe method by which the caps are produced and more particularly to capsmade of rubber material which are inexpensive to manufacture and adaptedto be applied to the bottles or other containers in a quick and simplemanner.

A further object of the invention is to provide a cap having asubstantially flat top portion 10 adapted to extend across the openingin the bottle and a depending skirt portion engageable with the bead orouter portion of the bottle for retaining the cap in place, which capbefore appli-' cation on the bottle has its skirt portion extend- 16 lngsubstantially parallel with the top portion and in relatively closerelation thereto thereby providing a normally fiat cap capable of beingstacked one upon the other in a minimum of space.

A still further object of the invention is to provide a cap of the typereferred to in which the skirt portion is greatly tensioned in itsapplication to the bottle but in which the top portion is app eciablyfree of tension to thereby permit expansion and contraction within thelimits required withoutafiecting the connection between the skirtportion and the bottle.

Another object of the invention is to provide a cap made from sheetrubber material and vulcanized and which may be made in any desiredcolor.

Additionally the invention contemplates the provision of a top portionof the cap made of transparent material tn enable unobstructed readingof the printing on the regular type of paper disc when used inconjunction with the present cap.

With the objects above indicated and other objects hereinafterexplained-in view, the invention consists in a cap construction andmethod by which the latter is produced.

Referring to the drawing:

Figure 1. is a top plan view of the present invention;

Figure 2 is a transverse sectional view taken on line 22 in Figure 1;

Figure 3 is a fragmentary sectional view of the neck portion of a bottleshowing the mannerin which the cap is rep'osed thereon;

Figures 4 to 6, inclusive, show steps in one method by which the cap maybe produced;

a cap embodying Figure 7 is a transverse sectional view of amodifiedform of cap embodying the present in'- ventlon. In the drawing,referring particularly to Figures 1 to 3, inclusive, a milk bottle capi0 is shown which may be made of rubber material or other similaryieldable material, and comprises a top portion H which is substantiallyflat and in this instance of circular shape approximately the size 5 ofthe bottle to which it is to be attached. A skirt portion ll of similarshape has its marginal edge secured to the adjacent marginal edge of thetop portion II in any suitable manner but preferably by vulcanization.

The skirt portion l2 normally extends in substantial parallelism withthe top portion II and is provided with an opening l3 preferablycentrally arranged. The caps ID are made relatively fiat so that theymay be stacked one upon the other with their skirt portions l2positioned upon their under sides to afford ready application to thebottles. The cap ID, as made, is free of any inherent tension in the topportion l l and skirt portion l2 for a purpose to be later described.

In Figure 3 a glass milk bottle I of the wellknown type is shown and hasa neck portion I5 providing an opening through which the milk may beintroduced into the bottle. A peripheral shoulder I6 is provided uponthe inner side of the neck portion adjacent the open end and is adaptedto receive the usual paper cap or closure to prevent the milk fromaccidentally spilling from the bottle. A circumferential bead l! is 30formed on the outside of the bottle adjacent the open end which isintended to function as a gripping portion to permit the bottle to bereadily picked up so it can be moved from one place to another.

In applying the cap ID to the bottle H, the skirt portion I2 isstretched by gripping the latter around the opening l3 until it passesfreely over the bead H on the end of the bottle. The lower edge of theskirt is then released and it grips the bead l1 assuming the shape shownin Figure 3, or any other shape the bead may have, because ofitsyieldability or being made of rubber. It is frictionally maintainedin contact with the head I! and, being under tension, prevents acci- 45dental disengagement. Due to the fact that the skirt portion I2 isoriginally made flat and substantially' parallel with the top portionII, the v greatest tension exerted at the lower edge adjacent theopening l3 and decreases from this point toward the marginal connectionwith the top portion II. This decrease in tension is desirablebecause itis practically non-stretched at the marginal edge with the result thatno tension is presentin the top portion II. The top portion tion is notunder tension and therefore the milk will probably not leaktherethrough. The cap will also stand chafing and will not tear becausethe top is free of tension. The skirt portion which is under tensionadheres to the bottle.

By providing a top portion H which is free from tension breathing ispermitted, which consists of expansion and contraction of the contentswithin the bottle due to temperature changes resulting in a flexing ofthe top portion in opposite directions, without any possibility ofdisengaging the cap from the bottle.

The cap may be made in various colors or combinations of colors byadding pigments to the unvulcanized rubber in a manner well-known in theart and combinations of materials may be employed such as a rubber skirtportion connected to a top portion formed of arubber hydrohalide filmsuch as that disclosed in Calvert Patent No. 1,989,632, dated January29, 1935, which is a product made by The Goodyear Tire 8: Rubber Companyunder the trade name Pliofilm. Additionally the entire cap may be madeof this rubber hydrohalide film material and, being transparent, hasmany advantages.

These caps l0 may be easily applied to bottles, preferably by machineoperation, and for convenience the caps l0 may be placed in a tubularcontainer with one cap upon the other. One end of the container may beopen to permit withdrawal of the caps, one at a time, with the skirtportion down and positioned adjacent the top of the bottle for readyapplication.

The cap i0 may be made by various processes, but one which I have foundvery desirable is to use unvulcanized or uncured calendered sheetrubber'material, the steps of this process being shown in Figures 4 to6, inclusive. A sheet l8 of unvulcanized rubber of the desiredthickness, preferably .015" to .02", is placed between cooperating diesI9 and 20, the lattr having an opening 2| therein of the desired size.The upper die I9 is then moved toward the lower die 20 and has a taperedportion 22 which enters the opening 2| as shown in dotted lines inFigure 4. This punches the hole l3 in the skirt portion of the cap l0and, while only one hole is here shown, it should be understood that thesheet l8 may be provided with many such holes.

After the punching operation a different upper die 23 is provided whichhas a recessed portion 24 formed upon its under side as shown in Figure5. This recessed portion is circular in shape to correspond with theshape of the top of the bottle and of approximately the same diameter. Asheet 25 of unvulcanized or uncured rubber of the desired thickness,preferably .01", is placed upon the underside of the die 23, insuperimposed relation with respect to the sheet I8, and a portion of thesheet is drawn up into the recessed portion 24 by means of vacuumeffective through the provision of an opening 26 in the die 23. Thisopening may be connected to any suitable source for the purposeintended.

I The-dies 20 and 23 are then moved into engagement as shown in Figure 6and the cap is cut out of the sheets leaving the top portion H and theskirt portion l2 connected together at their marginal edges. To effect aproper seal or connection the underside of the die 23 is taperedupwardly and inwardly, as shown at 21, at the desired angle to cause themarginal edges to cohere. Here again only one die 23 is shown, but itshould be understood that a plurality of dies may be used which shouldalign with the openings provided in the sheet l8. For productionpurposes a plurality of such dies is preferable.

The caps are then removed from the dies on separation of the latter andvulcanized according to any well known method. Preferably the caps arefirst dusted with soapstone or similar material to prevent stickingtogether and are then placed in a tubular container one on top of theother with the skirt portions extending in the same direction. This maybe the container in which the caps are shipped, or otherwise, and whenthe container has been filled it is slowly rotated about its axis in thepresence of warm air to vulcanize or cure the rubber. Rotating the capsprevents them from adhering to one another and the formation of flatspots thereon.

The caps may also be cured in a temperature of approximately 150 F. fora period of eight hours. Suitable accelerators of course areincorporated in the unvulcanized sheets of rubber to speed up thevulcanization process according to what process is used.

In Figure 7 a cap made of Pliofilm is shown having a top portion 28 andskirt portion 29 having an opening 30 therein. These caps are blankedout according to the hereinbefore stated process, but to form the sealbetween the marginal edges local heat is applied sufliciently to causethe edges to slightly melt and become joined together.

Whenthe cap is made from Pliofilm" and uncured rubber, localized heat islikewise used to form the seal, but the rubber portion is afterwardscured at a low temperature of approximately 120 F. for a period ofapproximately 48 hours. This low temperature is used so that thePliofilm will be unaffected by the vulcanizing of the rubber as it willstand a small amount of heat without injury.

With the Pliofilm caps it is sometimes necessary that they be heated toapproximately F. for eflicient application to the bottles, but with therubber caps this, of course, is not necessary as the rubber caps stretchsufliciently for application without permanent distortion.

While I have described the preferred embodiment of the invention it isto be understood that I am not to be limited thereto, inasmuch aschanges and modifications may be resorted to without departing from thespirit of the invention as defined in the appended claims.

What is claimed is:

1. A milk bottle cap comprising a pair of substantially fiat discsconnected at their marginal edges and extending in substantialparallelism, one of said discs having a transverse opening therethrough.

2. A milk bottle cap of rubber material comprising a pair ofsubstantially flat discs connected at their marginal edges and extendingin substantial parallelism, one of said discs having a transverseopening therethrough.

3. A milk bottle cap comprising a pair of substantially flat discsconnected at their marginal edges and extending in substantialparallelism, one of said discs-having a transverse opening therethroughand one of said discs being transparent.

4. A milk bottle cap of transparent material comprising a pair ofsubstantially flat discs connected at their marginal edges and extendingin substantial parallelism, one of said discs having a transverseopening therethrough.

5. A milk bottle cap of vulcanized rubber material comprising a pair ofrelatively flat discs connected at their marginal edges, one of saiddiscs having a transverse opening therethrough.

6. A milk bottle cap comprising a pair of relatively flat discsconnected at their marginal edges, one of said discs having a transverseopening therethrough.

7, A milk bottle cap of non-porous material comprising a pair ofrelatively fiat discs connected at their marginal edges, one of saiddiscs having a transverse opening therethrough.

8. A milk bottle cap comprising a pair of relatively fiat discs ofdifl'e'rent thicknesses connected at their marginal edges, one of saiddiscs having a transverse opening therethrough.

9. A milk bottle cap comprising a substantially flat top portion, and aflat op'en bottomportion having its marginal edge connected to said topportion, said top and bottom portions extending in substantialparallelism and being substantially in engagement with each other.

10. A milk bottle cap of flexible material comprising, a substantiallytensionless flat top portion adapted to extend across the opening in abottle, and a normally tensionless fiat bottom portion disposed insubstantial parallelism with said top portion and having a transverseopening

